Method for detecting pattern offset amount of exposed regions and detecting mark

ABSTRACT

A method for detecting a pattern offset amount of exposed regions comprises forming at least one pair of conductive detecting marks with a predetermined position relationship by a patterning process including two exposing processes; detecting an electrical characteristic of the at least one pair conductive detecting marks, if the detected electrical characteristic does not meet a predetermined position relationship, it is determined that the pattern offset amount of the exposed regions in two exposure steps is not qualified; and if the detected electrical characteristic meets the predetermined position relationship, it is determined that the pattern offset amount of the exposed regions in two exposure steps is qualified.

BACKGROUND

Embodiments of the present invention relates to a method for detecting apattern offset amount of exposed regions and a detecting mark.

Thin film transistor liquid crystal displays (TFT-LCDs) have theadvantages of small volume, low power consumption, low radiation and thelike, and thus have predominated in the current flat plate displaymarket.

A TFT-LCD is formed by bonding an array substrate and a color filtersubstrate together. On the array substrate, gate lines and signal linesare formed to intersect with one another so as to define pixel regions,and a pixel electrode and a thin film transistor are arranged in eachpixel region.

In the current manufacturing processes of a TFT-LCD, the differentregions in the same structure layer sometimes need to be respectivelyexposed, and at this time, a pattern offset amount of exposed regions inthe same structure layer need to be detected so as to ensure the uniformarrangement of patterns of the exposed regions.

In one detecting or testing process as shown in FIG. 1, when a firstregion 1 is exposed, besides photoresist patterns for a array structureare formed, a sets of photoresist patterns 2 not exposed aresimultaneously formed for detecting marks in the periphery of the firstregion 1, and shape of the photoresist patterns 2 may be a rectangle, acircle and the like (as shown in FIG. 1 (a)). Then, when a second region3 is exposed in the same layer, besides that photoresist patterns forthe array structure are formed in the second region 3, the patterns 2formed in the previous exposure process are again exposed so as to formphotoresist patterns 4 subject to exposure and each slightly smallerthan patterns 2 (as shown in FIG. 1(b)). When a pattern offset amountbetween the two exposing processes is in a specified range, the patterns4 are located inside of the patterns 2, and after the photoresist isdeveloped, the patterns 4 and 2 form ring shape structures. Patternoffset amounts at the upper portion, the lower portion, the left portionand the right portion of each ring shape structure can be respectivelydetected by a microscope, a camera, an image processing device and thelike, and thus, the pattern offset amount can be determined.

However, it takes long time to detect the pattern offset amount ofexposed regions in the above process, and thus a full detection of aglass substrate is difficult to be achieved, a missing detection easilyoccurs, and a defective product may unintentionally enter subsequentprocesses.

SUMMARY

An embodiment of the present invention relates to a method for detectinga patter offset amount of exposed regions, comprising: forming at leastone pair of conductive detecting marks with a predetermined positionrelationship by a patterning process including two exposing processes;detecting an electrical characteristic of the at least one pairconductive detecting marks, if the detected electrical characteristicdoes not meet a predetermined position relationship, it is determinedthat the pattern offset amount of the exposed regions in two exposuresteps is not qualified; and if the detected electrical characteristicmeets the predetermined position relationship, it is determined that thepattern offset amount of the exposed regions in two exposure steps isqualified.

Another embodiment of the present invention relates to a detecting markfor detecting a pattern offset amount of exposed regions, comprising: aconductive first detecting mark and a conducive second detecting mark,disposed in pair at a periphery region of the exposed regions, whereinthe first detecting mark and the second detecting mark are located inthe same layer, and the first detecting mark and the second detectingmark are spaced a specified distance from each other and are insulatedfrom each other.

Further another embodiment of the invention provides a detecting markfor detecting a pattern offset amount of exposed regions, comprising: aconductive first detecting mark and a conducive second detecting mark,disposed in pair at a periphery region of the exposed regions indifferent layers; and an insulating layer interposed between the firstdetecting mark and the second detecting mark; wherein the firstdetecting mark and the second detecting mark are located at apredetermined relative position in the different layers.

Further scope of applicability of the present invention will becomeapparent from the detailed description given hereinafter. However, itshould be understood that the detailed description and specificexamples, while indicating preferred embodiments of the invention, aregiven by way of illustration only, since various changes andmodifications within the spirit and scope of the invention will becomeapparent to those skilled in the art from the following detaileddescription.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description given hereinafter and the accompanying drawingswhich are given by way of illustration only, and thus are not limitativeof the present invention and wherein:

FIGS. 1 (a) and (b) are schematic views for showing a detecting ofpattern offset amount of exposed regions in the related art;

FIG. 2 is a forming schematic view of a first detecting mark accordingto embodiments of the present invention;

FIG. 3 is a forming schematic view of a second detecting mark accordingto embodiments of the present invention;

FIG. 4 is a schematic view of a detecting mark according to embodimentsof the present invention;

FIG. 5 is a schematic view of a detecting mark of a substrate accordingto embodiments of the present invention;

FIGS. 6 (a) and (b) are schematic views of detecting marks according toembodiments of the present invention;

FIG. 7 is a schematic view for showing a corresponding relationshipbetween the first detecting mark and the second detecting mark accordingto embodiments of the present invention; and

FIG. 8 is another schematic view for showing the correspondingrelationship between the first detecting mark and the second detectingmark according to embodiments of the present invention.

DETAILED DESCRIPTION

Some embodiments of the invention will be described hereinafter withreference to the accompanying drawings. Obviously, the embodiments to bedescribed are only a part but not all of the embodiments of theinvention. All other embodiments obtained by those skilled in therelevant technical field based on the described embodiments withoutinventive work should be included in the scope of the present invention.

A method for detecting a pattern offset amount of exposed regionsaccording to one embodiment of the present invention comprises:

S201, forming at least one pair of conductive detecting marks having apredetermined position relationship by a patterning process includingtwo exposing processes.

S202, detecting an electric characteristic of the at least one pair ofconductive detecting marks, and if the detected electric characteristicdoes not meet a predetermined position relationship, it is determinedthat the pattern offset amount of exposed regions in the two exposingprocesses is not qualified; if the electric characteristic meets thepredetermined position relationship, it is determined that the patternoffset amount of exposed regions in two exposing processes is qualified.

In the method for detecting pattern offset amount of exposed regionsprovided by the present embodiment, the pattern offset amount inexposing processes is detected by means of electric characteristic, andthus the detection can be performed rapidly and in real-time, the fulldetection on a substrate can be achieved, and the defect detection rateand yield can be improved.

A patterning process typically includes depositing a thin film, applyingphotoresist on the thin film, exposing and developing of thephotoresist, etching the thin film by using formed photoresist mask,removing remaining photoresist, and etc.

With regarding to the method for detecting pattern offset amount ofexposed regions according to the present embodiment, detection of apattern offset amount of a plurality of exposure regions in a same layeris described as an example, and the exemplary method comprises:

S301, sequentially forming a conductive thin film and a photoresistlayer on a substrate. This photoresist layer is used to pattern theconductive thin film so as to form a required circuit pattern and thelike.

S302, exposing a first region of the photoresist layer and a peripheryregion of the first region, a photoresist pattern which is not exposedin the periphery region of the first region includes a patterncorresponding to at least one first detecting mark.

As shown in FIG. 2, when the first region 1 is exposed, the photoresistpatterns not exposed at an upper portion, a middle portion and a lowerportion of a periphery (in present embodiment, only a right side isshown) of the first region 1 have three zigzag shape patterns for thefirst detecting marks 6. Each of the first detecting marks 6 includes aleft part and a right part disposed separately, and the first detectingmark 6 cab further include a connection terminal 8 used to apply atesting current.

S303, exposing a second region of the photoresist layer and a peripheryregion of the second region, and a photoresist pattern which is notexposed in the periphery region of the second region includes a patterncorresponding to at least one second detecting mark, wherein a patternof one first detecting mark and a pattern of one second detecting markare disposed in pair and are spaced a specified distance from each otheraccording to a design requirement.

Based on the FIG. 2, as showing in FIG. 3, when a second region 3 of thesame photoresist layer is exposed, and a photoresist pattern which isnot exposed in the periphery region of the second region includes a “

” (of Chinese character) shaped pattern for one second detecting mark 7to used to achieve the second detecting mark 7 in a “

” shape. Each “

” shaped pattern is in connection with the pattern of one firstdetecting mark 6 and is spaced a specified distance from the pattern ofthis first detecting mark 6. In the example as shown, the patterns forthe second detecting marks 7 also include three patterns located at theupper portion, the middle portion and the lower portion respectively,and one of the three patterns forms one pair with one photoresistpattern for the first detecting marks 6, and is located between the leftpart and the right part, disposed oppositely, of the photoresist patternof the first detecting mark 6, and thus each resultant second detectingmark 7 is surrounded by the corresponding first detecting mark 6. Thesecond detecting mark 7 also can further have a connection terminal 8for supplying a detecting current. According to the design requirement,the pattern of the second detecting mark 7 and the pattern of the firstdetecting mark 6 are not connected to each other, and a longitudinalpredetermined interval “a” and a transverse predetermined interval “b”between them are both set according to the technical standard. Inpractice, if a pattern offset amount of two exposing processes does notmeet the requirement, the pattern of the second detecting mark 7 may beconnected to the pattern of the first detecting mark 6.

S304, after developing the photoresist, etching the conductive thin filmand removing the photoresist on the substrate, the first and seconddetecting marks formed of the conductive thin film are obtained.

With regard to the detecting marks, firstly, the exposed photoresistlayer is developed so as to remove the exposed portions of thephotoresist layer, and only the photoresist patterns for the detectingmarks, which are not exposed, are remained; then, the underlyingconductive thin film is etched by using the photoresist patterns as anetching mask to etch out the portions not covered by the photoresist ofthe conductive thin film, and only the portions covered by photoresistand for the detecting marks of the conductive thin film are remained;finally, the photoresist patterns are removed, the photoreist coveringthe etched conductive thin film is removed such that the conductivefirst and second detecting marks are obtained. According to the designrequirement, each first detecting mark and the corresponding seconddetecting mark are insulated from each other; however, if a patternoffset amount of two exposing processes does not meet the designrequirement, the first detecting mark and the second detecting mark maybe connected to each other.

S305, performing detection by supplying current to the conductive firstand second detecting marks, and if the current flows between the firstdetecting marks and the second detecting marks, it is determined that apattern offset amount between the first region and the second region isnot qualified; if the first detecting mark and the second detecting markare insulated from each other, it is determined that the pattern offsetamount of between the first region and the second region is qualified.

More specifically, when a pattern offset amount of two continuousexposing processes for the different regions is in the range of aspecified standard, the first detecting marks 6 and the second detectingmarks 7 are insulated from each other, and at this time, if current isapplied to the connection terminal 8 of one first detecting mark 6, thecurrent cannot be detected out at the connection terminal 8 of thecorresponding second detecting mark 7; and if current is applied to theconnection terminal 8 of one second detecting mark 7, the current cannotbe detected out at the connection terminal 8 of the corresponding firstdetecting mark 6 as well.

On the contrary, if the pattern offset amount of two continuous exposingprocesses is not qualified and out of the standard range, portions ofthe first detecting marks 6 and the second detecting marks 7 along acertain direction overlaps with each other, which makes the firstdetecting marks 6 and the second detecting marks 7 electricallyconnected with each other. At this time, if current is applied to theconnection terminal 8 of one first detecting mark 6, current can bedetected out at the connection terminal 8 of the corresponding seconddetecting mark 7; and if current is supplied to the connection terminal8 of one second detecting mark 7, the current can be detected out at theconnection terminal 8 of the corresponding first detecting mark 6 aswell.

In the method for detecting a pattern offset amount of exposed regionsaccording to the present embodiment, two exposing processes are used toexpose different regions on the substrate, and then a developingprocess, an etching process and a removing process are used to form atleast a pair of conductive detecting marks which should be insulatedfrom each other, and current is applied to the pair of detecting marksto perform detection, if the detecting marks expected to be insulatedfrom each other are electrically connected to each other, it means thata pattern offset amount of the two exposed regions is not qualified; ifthe detecting marks exposed to be insulated from each other arecertainly insulated from each other, it means that the pattern offsetamount of the two exposed regions is qualified. The pattern offsetamount of exposed regions in the same layer is detected by means ofcurrent, and thus the detection is performed rapidly and in real-time,the full detection on a substrate can be achieved and the defectdetection rate and yield can be improved.

In the above mentioned embodiments, a kind of positive photoresist isused, wherein the exposed photoresist is removed and the photoresist notexposed is remained during the development process. However, in theembodiments of the present invention, the photoreist may be a kind ofnegative photoresist, wherein the exposed photoreist is remained and thephotoresist not exposed is removed during the development process, andthus the photoresist patterns corresponding to the first and seconddetecting marks are exposed, which is opposite to the above mentionedpositive photoresist.

In addition, as shown in FIG. 4, all of the conductive first detectingmarks 6 formed between the first region 1 and the second region 3 may beelectrically connected together, and correspondingly, all of theconducting second detecting marks 7 may be electrically connectedtogether. Thus, current is applied to any one pair of the firstdetecting mark 6 and the second detecting mark 7 to perform detection soas to obtain a pattern offset amount of the first region 1 and thesecond region 3, which is more rapid than a separate detection in theabove embodiment.

Further, for the entire glass substrate, all or a portion of the firstdetecting marks thereon may be electrically connected together and ledto an edge of the substrate by a lead wire. Correspondingly, all of aportion of the second detecting marks may be electrically connectedtogether and led to an edge of the substrate.

As shown in FIG. 5, connection terminals of all of the longitudinal andtransverse detecting marks 11 on a glass substrate 12 are electricallyconnected together and led to an edge of the glass substrate 12. All ofthe first detecting marks 6 may be electrically connected together andled to an edge pin 9 of the glass substrate 12, or the first detectingmarks 6 may be connected together and separately led to an edge pin 10of the glass substrate 12. The detection functions can be performedidentically in the above two cases.

Current is introduced into a pin at an edge of the glass substrate 12,and thus, a pattern offset amount of longitudinal exposed regions and apattern offset amount of transverse exposed regions can be convenientlydetected out, and the detection can be rapidly and more easilyperformed.

A portion of the detection marks on the glass substrate are connectedtogether, as an example, to explain the present embodiment, but all ofthe detecting marks may be connected to one another, that is, all of thefirst detecting marks 6 may be connected together and led to an edge ofthe substrate, and all of the second detecting marks 7 may also beconnected together and led to an edge of the substrate, and then,current is applied to perform detection.

It is noted that patterns of the detecting mark 6 and 7 in the exampleonly are the purpose of illustration, and the shape of the detectingmarks is not limited to that as shown, but various changes can be madewithout departing from the spirit of the present invention. For example,the concave-convex complementary patterns spaced a specified distancefrom each other as show in FIG. 6 (a) can be used, in which a seconddetecting mark is partially surrounded by a first detecting mark; or,the concentric ring patterns as shown in FIG. 6 (b) can be used, inwhich a second detecting mark is surrounded by a first detecting mark.

A method for detecting a pattern offset amount of exposed regionsaccording to the present embodiment may also be explained by takingdetection of a pattern offset amount of exposing processes in thedifferent layers as an example, and a method of the example comprises:

S901, sequentially forming a first conductive thin film and a firstphotoresist layer on a substrate. The first photoresist layer is used topattern the underlying first conductive thin film to form a circuitpattern and the like.

S902, exposing the first photoresist layer in a first region of thesubstrate and a periphery region of the first region, and thendeveloping the photoresist, etching the first conductive thin film andremoving the photoreist, whereby at least one conductive first detectingmark is obtained in the periphery region of the first region.

With regard to a region in which the detecting marks are formed, andsimilarly to the above embodiment, firstly, the photoresist layer isdeveloped, and the exposed portion of the photoresist is removed andonly a portion not exposed and corresponding to the detecting markpatterns of the photoresist is remained. Then, the first conductive thinfilm is etched by using the resultant photoresist mask, and a portion,not covered by the photoreist, of the conducive thin film is etched out,and only a portion, covered by the photoresist pattern for the detectingmark, of the conductive thin film is remained. Finally, the remainingphotoresist is removed, that is, the photoresist covering the etchedconductive thin film is stripped away, and thus, at least one conductivefirst detecting mark is obtained.

S903, sequentially forming a second conductive thin film and a secondphotoresist layer in another layer on the substrate. The secondphotoresist layer is used to pattern the underlying second conductivethin film to form a circuit pattern and the like

S904, exposing the second photoresist layer in the first region and aperiphery region of the first region, and then developing thephotoresist, etching the second conductive thin film and removing thephotoreist, whereby at least one conductive second detecting mark whichis in a pair with the first detecting mark is obtained in the peripheryregion of the first region, and an insulating layer is formed betweenthe second detecting mark and the first detecting mark.

Herein, the detailed process for forming the second detecting mark isthe same as that for forming the first detecting mark, so it is omitted.

Herein, there are two corresponding relationships between the seconddetecting mark and the first detecting mark.

The first corresponding relationship is shown in FIG. 7, in which asecond detecting mark 1002 of a first region 201 in a second layer iscompletely overlapped with a first detecting mark 1001 of a first region101 in a first layer, that is, an overlapping area of two detectingmarks is at maximum at an initial stage.

The second corresponding relationship is shown in FIG. 8, in which asecond detecting mark 1102 of a first region 201 in a second layer isnot overlapped with a first detecting mark 1101 of a first region 101 ina first layer, that is, an overlapping area of two detecting marks iszero at an initial stage.

It should be noted that in FIGS. 7 and 8, the insulating layer betweenthe two detecting marks is omitted for clarity.

S905, detecting capacitance between the first detecting mark and thesecond detecting mark, and if a difference between the capacitance and aspecified value is within a specified range, it can be determined that apattern offset amount between the first regions in the two layers isqualified, and if the difference between the capacitance and thespecified value is out of the specified range, it can be determined thatthe pattern offset amount between the first regions in the two layers isnot qualified.

Here, for detecting a pattern offset amount of exposing processes in thedifferent layers, since conductive thin films in the different layersare isolated from each other by an insulating layer, current detectioncan not be performed in the manner described in the above embodiment.However, an alignment offset occurs between the positions of exposedregions in the different layers, a corresponding position of the firstdetecting mark and the second detecting mark changes, and an overlappingarea of the first detecting mark and the second detecting mark maycorrespondingly increase or decrease. Thus, a pattern offset amount ofexposed regions in two photoresist layers can be detected by means ofcapacitance.

More specifically, a calculating equation of capacitance is: C=AS/d,wherein “A” is a parameter related to medium, S is an overlapping area,and d is a distance between conductive thin films of the first detectingmark and the second detecting mark. When conductive thin films of eachtwo layers are not overlapped with each other, the capacitance is verysmall and can be substantially omitted. When an alignment offset occursbetween each two layers and an overlapping area S is generated,capacitance different can be detected out, and thus it can be determinedwhether the alignment offset occurs and to what degree the alignmentoffset is.

For example, with regarding to the first corresponding relationship asshow in FIG. 7, at an initial stage, an overlapping area of the firstdetecting mark 1001 and the second detecting mark 1002 is at themaximum, that is, S in the equation is at the maximum, and capacitanceof the formed capacitor is at the maximum at the initial stage (aspecified value is set to A). When a pattern offset amount of exposedregions of two layers is zero or very slight, a change of theoverlapping area of the two detecting marks is zero or very small, adetected capacitance is substantially similar to the specified value A,that is, a difference between the detected capacitance and the specifiedvalue A is within a specified range, and thus, it can be determined thata pattern offset amount of exposed regions in two layers is qualified.When a pattern offset amount of exposed regions in two layers isrelatively large, a change of the overlapping area of the two detectingmarks is relatively large, and thus, it can be determined that a patternoffset amount of exposed regions in two layers is not qualified.

With regarding to the second corresponding relationship shown in FIG. 8,an initial overlapping area of two detecting marks is at the minimum,and a principle thereof is the same as the second correspondingrelationship, so it is omitted for simplicity. The detecting marks inthe layers can be connected to each other by via holes.

In additional, each of the conductive first detecting marks at theperiphery of the first region in a first layer may be connected to oneanother; and each of the conductive second detecting marks at theperiphery of the first region in a second layer may be correspondinglyconnected to one another. Thus, by detecting capacitance between any onepair of the first and second detecting marks, a pattern offset amount ofthe first layer and the second layer can be obtained, which is morerapidly than the separate detection.

Further, for the entire glass substrate, all or a portion of the firstdetecting marks in the first layer may be electrically connected to oneanother and led to an edge of the substrate by a lead wire.Correspondingly, all of a portion of the second detecting marks may beelectrically connected to one another and led to an edge of thesubstrate. Thus, the detection may be quicker and more convenient.

It should be noted that the detecting marks 1001, 1002, 1101, and 1102in the present embodiment are given only as an example, and thedetection marks are not limited thereto but may be varied withoutdeparting from the spirit of the present invention. For example, anupper and lower two detecting marks may be in concave-convexcomplementary patterns, concentric ring patterns or the like, as shownin FIGS. 6(a) and 6(b). In the above mentioned example, a kind ofpositive photoresist is still used as an example, but a kind of negativephotoresist may be used.

In addition, pattern offset amount detection for two layers provided bythe present embodiment can be performed separately, that is, detectingmarks may be specially designed for this detection, and the above firstcorresponding relationship or the second corresponding relationship maybe selected for the detecting marks.

Or, the detecting marks for detecting a pattern offset amount by usingcurrent in the same layer may be repeatedly used for detection of apattern offset amount between different layers; that is, in each layer,the same detecting marks for current detection is formed, and afterdetection a pattern offset amount for the same layer is performed,detection of a pattern offset amount between different layers then isperformed, and at this time, a relationship between the detecting marksin two layers can be the above first corresponding relationship. Therelated detecting marks may be similar to the above-described detectingmarks 6 and 7, or may be similar to those shown in FIG. 4.

A detecting mark for detecting a pattern offset amount of exposedregions provided in embodiments of present invention are shown in FIG.3, and the detecting marks includes a conductive first detecting mark 6and a conductive second detecting mark 7 which are disposed in pair at aperiphery region of the exposed regions 1 and 3. The first detectingmark 6 and the second detecting mark 7 are located in the same layer,and during the manufacturing process, the detecting mark 6 and thesecond detecting mark 7 are spaced a specified distance “a” and “b” fromeach other according to a design requirement and are insulated from eachother.

Further, the first detection mark 6 and the second detection mark 7 mayrespectively include connection terminals 8 for applying current. Thesecond detection mark 7 may be partially or all surrounded by the firstdetecting mark 6.

Detecting marks for detecting a pattern offset amount of exposed regionsprovided in the embodiments of present invention can used to detect apattern offset amount by applying current to the first and seconddetecting marks. If the detecting marks expected to be insulated fromeach other are insulated from each other, it means that the patternoffset amount of the exposed regions is qualified; if the detectingmarks are electrically connected to each other, it means that thepattern offset amount of the two exposed regions is not qualified. Thepattern offset amount of exposed processes is detected by using anelectrical characteristic, and thus, the detection can be performedrapidly and in real-time, the full detection on a substrate can beachieved, and the defect detection rate and yield can be improved.

As shown in FIG. 7, detecting marks for detecting a pattern offsetamount of exposed regions provided in embodiments of present inventioninclude a conductive first detecting mark 1001 and a conductive seconddetecting mark 1002 which are disposed in pair at a periphery region ofexposed regions 101 and 102 in different layers. The first detectingmark 101 and the second detecting mark 102 are located at specifiedpositions in the different layers, and an insulating layer (not shown)is interposed between the first detecting mark 101 and the seconddetecting mark 102.

Further, the first detection mark 1001 and the second detection mark1002 may respectively include connection terminals (not shown) forapplying a voltage.

Detecting marks for detecting a pattern offset amount of exposed regionsprovided in embodiments of present invention may detect a pattern offsetamount of the exposed regions in different layers by applying a voltageto the first and second detecting marks and determining capacitancedifference between the two detecting marks, if a difference between thecapacitance and the specified value is within a specified range, it canbe determined that a pattern offset amount of two layer is qualified; ifa difference between the capacitance and the specified value is out ofthe specified range, it can be determined that a pattern offset amountof two layer is not qualified. The pattern offset amount of exposedprocesses can be detected by using an electrical characteristic, andthus, the detection can be performed rapidly and in real-time, the fulldetection on a substrate can be achieved, and the defect detection rateand yield can be improved.

It should be noted that, the embodiments described above are intended toillustrate but not limit the present invention; although the presentinvention has been described in detail herein with reference to theabove mentioned embodiments, it should be understood by those skilled inthe art that the present invention can be modified and some of thetechnical features can be equivalently substituted without departingfrom the spirit and scope of the present invention.

What is claimed is:
 1. A method for detecting a pattern offset amount ofexposed regions, comprising: forming at least one pair of conductivedetecting marks with a predetermined position relationship by apatterning process including two exposing processes; detecting anelectrical characteristic of the at least one pair conductive detectingmarks, if the detected electrical characteristic does not meet apredetermined position relationship, it is determined that the patternoffset amount of the exposed regions in two exposure steps is notqualified; and if the detected electrical characteristic meets thepredetermined position relationship, it is determined that the patternoffset amount of the exposed regions in two exposure steps is qualified,wherein forming at least one pair conductive detecting marks with apredetermined position relationship by a patterning process includingtwo exposing processes comprises: sequentially forming a firstconductive thin film and a first photoresist layer on a substrate;exposing a first region of the first photoresist layer and a peripheryregion of the first region, and then, developing the exposed firstphotoresist layer on the substrate to obtain a first photoresist maskand etching the first conductive thin film by using the firstphotoresist mask, and then removing the first photoresist mask, and thusat least one first detecting mark formed of the first conductive thinfilm is formed in the periphery region of the first region; sequentiallyforming a second conductive thin film and a second photoresist layer inanother layer on the substrate; and exposing a first region of thesecond photoresist layer and a periphery region of the first region, andthen, developing the exposed second photoresist layer on the substrateto obtain a second photoresist mask and etching the second conductivethin film by using the second photoresist mask, and then removing thesecond photoresist mask, and thus at least one second detecting markformed of the second conductive thin film is formed in the peripheryregion of the first region, wherein the second detecting mark and thefirst detecting mark are disposed in pair, and an insulating layer isformed between the second detecting mark and the first detecting mark.2. The method according to claim 1, wherein detecting an electricalcharacteristic of the at least one pair conductive detecting markscomprising: detecting capacitance between the first detecting mark andthe second detecting mark, wherein if a difference between thecapacitance and a specified value is within a specified range, it isdetermined that a pattern offset amount between the first regions of twolayers is qualified, and if the difference between the capacitance andthe specified value is out of the specified range, it is determined thatthe pattern offset amount between the first regions of two layers is notqualified.
 3. The method according to claim 1, wherein a plurality offirst detecting marks are formed and the conductive first detectingmarks are electrically connected to one another.
 4. The method accordingto claim 3, wherein a plurality of second detecting marks are formed andthe conductive second detecting marks are electrically connected to oneanother.
 5. The method according to claim 1, wherein a plurality offirst detecting marks and a plurality of second detecting marks areformed, and wherein a portion of the conductive first detecting marksare electrically connected to one another, and the second detectingmarks corresponding to the first detecting marks electrically connectedto one another are electrically connected to one another.